This competing continuation seeks to extend an ongoing longitudinal project (R01HD37007-01) examining the relations between preoperative anxiety and postoperative behavioral and clinical recovery in a population of children undergoing surgery. Over five million children undergo surgery in the United States. It is estimated that up to 75 percent of these children develop extreme anxiety prior to their surgery. In adults, extreme preoperative anxiety has been shown to correlate with postoperative clinical outcomes such as pain and analgesic requirements, and prolonged recovery and hospital stay. In children, excluding data from our initial application, there are no peer reviewed, published outcome data regarding the question of whether heightened preoperative behavioral stress and anxiety impairs postoperative recovery. This issue is of extreme importance as several effective interventions are available to treat preoperative anxiety in children. Unfortunately, there is currently a strong trend towards reduction in these preoperative interventions. This trend is most likely a result of the present medical-economic climate and the absence of outcome data in children documenting a link between preoperative anxiety and postoperative recovery. In our initial application, we have demonstrated that high levels of preoperative anxiety in children are associated with increased postoperative pain and impaired clinical and behavioral postoperative recovery. Thus, our results suggest that interventions aimed at the reduction of preoperative anxiety will improve the postoperative recovery process. Over the past several years our laboratory has developed and validated a number of such interventions. Thus, in the next phase of the study, we propose a randomized controlled trial that will examine the impact of various preoperative interventions on the postoperative behavioral and clinical recovery process. This will be assessed by convergent clinical, neuroendocrinological, and behavioral measures. As secondary aims we will (1) evaluate the impact of various types of preoperative interventions in children to the above hypothesis, and (2) examine the effectiveness and consistency of these preoperative interventions across various age groups. The broad, longterm objectives of this research are the evaluation, development and implementation of preoperative interventions that will improve the postoperative behavioral and clinical recovery process.